Multipivot Flight Control Interface for Jam-Tolerant Fly-By-Wire Input
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Fly-by-wire aircraft systems face challenges in maintaining control redundancy and resilience against single-point failures in human machine interfaces, particularly in transitioning to single-pilot operations, where mechanical linkages are susceptible to jams or impairments.
Innovation Solution
A multipivot user interface device with independently rotatable linkages and a sensing arrangement to measure orientation angles, allowing continued operation even if one linkage is jammed, by compensating with the other linkage to maintain control commands.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If single-pilot operations are implemented to reduce cockpit complexity, then device complexity is reduced, but reliability deteriorates due to loss of redundant control systems
Solution Approach 1:
The control stick is divided into multiple independent linkages (first linkage, second linkage, third linkage) that can operate independently. Each linkage has its own pivot points and sensing elements, allowing the system to segment the control function across multiple redundant mechanical paths while maintaining a single-pilot configuration.
Solution Approach 2:
The system incorporates redundant linkages and sensing arrangements before any failure occurs. The multiple linkages are designed to compensate for potential jams or impairments in individual linkages, providing beforehand cushioning against single-point failures and maintaining reliability without requiring dual-pilot operations.
2Ease of operation
If mechanical linkages are used for control input, then ease of operation is maintained through intuitive physical control, but reliability deteriorates due to susceptibility to jams and mechanical impairments
Solution Approach 1:
Different linkages are positioned and configured with specific pivot points and orientation ranges to provide localized control functions. The first linkage handles primary control inputs while the second and third linkages provide redundant control paths with different mechanical characteristics, allowing the system to maintain intuitive control while compensating for mechanical failures through differential linkage design.
Solution Approach 2:
The redundant linkage system is designed beforehand to compensate for potential mechanical failures. If one linkage becomes jammed or impaired, the sensing arrangement detects the failure and compensates using the remaining functional linkages, providing beforehand cushioning against mechanical reliability issues while maintaining ease of operation.
3Reliability
If redundant linkages are added to maintain control reliability, then reliability is improved through fail-operational capability, but device complexity increases
Solution Approach 1:
Multiple linkages and sensing elements are merged into a single integrated control stick assembly. The first, second, and third linkages are combined with a unified sensing arrangement that processes inputs from all linkages simultaneously, allowing the system to achieve control redundancy through merging rather than through separate independent systems, thereby reducing overall device complexity.
Solution Approach 2:
The sensing arrangement is designed with multi-functionality to handle inputs from multiple different linkage configurations. It can process control inputs whether one, two, or all three linkages are functional, allowing the same sensing system to serve multiple redundancy scenarios without requiring separate sensing systems for each redundancy level, thus avoiding increased device complexity.
Data Source
Figure 1
Figure 2
Figure 3
AI summary
Fly-by-wire vehicle systems and related user interface devices are provided for controlling operation of a vehicle, such as an aircraft. An exemplary user interface (200) includes a first linkage (202) and a second linkage (204) coupled to the first linkage. The first linkage is actuatable about a first pivot point (206) and the second linkage is actuatable about a second pivot point (208) independent of actuation of the first linkage about the first pivot point. The user interface includes a sensing arrangement configurable to obtain a first orientation of the first linkage with respect to a first reference orientation associated with the first pivot point, obtain a second orientation of the second linkage with respect to a second reference orientation associated with the second pivot point, and determine an input command based at least in part on the first orientation and the second orientation.